With T rated tyres fitted have a accident and if the insurance Co find out they will not pay.

I don’t think so , as long as you are not exceeding the speed / load rating of a tyre then why should they not pay out . Ooh sorry I had a parking bump , sorry your tyres are not suitable. Many years in the motor industry I have never known anybody look at tyres apart from tread depth during an insurance claim .

Then if you fit anything other than a 185 X 80 X 14 Hr tyre onto a standard rim then you should tell them it’s not standard . I bet 99% of people on here have non HR standard size tyres and non standard rims and don’t tell the insurance company . They will only be interested if your silly or stupid with tyre size , condition and maybe even more so now tyre age .

I have told my insurance Co everything which is none standard - standard wheels with winter tyres fitted during the winter and 7" wolfs fitted with 195x65x14 tyres fitted in the summer ( MB ) - not worth the risk IMO for the want of a bit of typing on the insurance form.